Water retention and gas ingestion control for a fuel cell

Abstract

A fuel cell includes a water transport plate providing a water flow field. The water flow field includes water having gas. A vent is in fluid communication with the water flow field. The vent includes a membrane that obstructs flow of water past the membrane while permitting the flow of gas past the membrane. The membrane can include a pore size between approximately 0.1μ to 10.0μ, which enables gases to pass through the pores while blocking water. The membrane can be hydrophobic, for example, Teflon, to prevent the passage of water through the membrane. A hydrophobic fluid can also be arranged on the membrane to act as a check valve.

1 . A fuel cell comprising:
 a water transport plate providing a water flow field, the water flow field including water having gas; and   a vent in fluid communication with the water flow field, the vent including a membrane obstructing flow of the water past the membrane while permitting the flow of the gas past the membrane, wherein the membrane includes a fluorine-based polymer.   
     
     
         2 . The fuel cell according to  claim 1 , comprising a cathode and anode, water from the water transport plate passing through at least one of the cathode and anode. 
     
     
         3 . The fuel cell according to  claim 2 , comprising a cooling loop in fluid communication with the water flow field that receives water vapor, the cooling loop including a condenser for condensing the water vapor to liquid water, a separator for separating a the water vapor and liquid water, and a return line for supplying the liquid water to the water flow field. 
     
     
         4 . The fuel cell according to  claim 1 , wherein the water flow field includes inclined walls guiding the gas to the vent. 
     
     
         5 . The fuel cell according to  claim 1 , wherein the membrane is hydrophobic. 
     
     
         6 . The fuel cell according to  claim 1 , wherein the fluorine-based polymer includes Teflon. 
     
     
         7 . The fuel cell according to  claim 1 , comprising:
 a membrane electrode assembly;   a first separator plate disposed on a first side of the membrane electrode assembly;   a second separator plate disposed on a second side of the membrane electrode assembly opposite the first side;   wherein at least one of the first separator plate and second separator plate has a porous section, wherein at least one of the first separator plate and second separator plate have a reactant flow field disposed thereon; and   a water flow field in fluid communication with the porous section of the at least one of the first separator plate and second separator plate.   
     
     
         8 . A fuel cell comprising:
 a water transport plate providing a water flow field, the water flow field including water having gas; and   a vent in fluid communication with the water flow field, the vent including a membrane obstructing flow of the water past the membrane while permitting the flow of the gas past the membrane, wherein the membrane has a pore size of between approximately 0.1μ to 10.0μ.   
     
     
         9 . The fuel cell according to  claim 8 , wherein the membrane has a pore size of between approximately 0.1μ to 5.0μ. 
     
     
         10 . The fuel cell according to  claim 9 , comprising a cathode and anode, water from the water transport plate passing through at least one of the cathode and anode. 
     
     
         11 . The fuel cell according to  claim 10 , wherein the water flow field includes inclined walls guiding the gas to the vent. 
     
     
         12 . The fuel cell according to  claim 9 , wherein the membrane is hydrophobic. 
     
     
         13 . The fuel cell according to  claim 9 , comprising:
 a membrane electrode assembly;   a first separator plate disposed on a first side of the membrane electrode assembly;   a second separator plate disposed on a second side of the membrane electrode assembly opposite the first side;   wherein at least one of the first separator plate and second separator plate has a porous section, wherein at least one of the first separator plate and second separator plate have a reactant flow field disposed thereon; and   a water flow field in fluid communication with the porous section of the at least one of the first separator plate and second separator plate.   
     
     
         14 . A fuel cell comprising:
 a water transport plate providing a water flow field, the water flow field including water having gas; and   a vent in fluid communication with the water flow field, the vent including a membrane obstructing flow of the water past the membrane while permitting the flow of the gas past the membrane, wherein the membrane separates a passage into first and second sides, the water arranged on the first side, and a hydrophobic liquid arranged on the second side.   
     
     
         15 . The fuel cell according to  claim 10 , wherein the hydrophobic liquid is exposed to atmosphere. 
     
     
         16 . The fuel cell according to  claim 14 , comprising a cathode and anode, water from the water transport plate passing through at least one of the cathode and anode. 
     
     
         17 . The fuel cell according to  claim 16 , comprising a cooling loop in fluid communication with the water flow field that receives water vapor, the cooling loop including a condenser for condensing the water vapor to liquid water, a separator for separating a the water vapor and liquid water, and a return line for supplying the liquid water to the water flow field. 
     
     
         18 . The fuel cell according to  claim 14 , wherein the water flow field includes inclined walls guiding the gas to the vent. 
     
     
         19 . The fuel cell according to  claim 14 , wherein the membrane is hydrophobic. 
     
     
         20 . The fuel cell according to  claim 14 , comprising:
 a membrane electrode assembly;   a first separator plate disposed on a first side of the membrane electrode assembly;   a second separator plate disposed on a second side of the membrane electrode assembly opposite the first side;   wherein at least one of the first separator plate and second separator plate has a porous section, wherein at least one of the first separator plate and second separator plate have a reactant flow field disposed thereon; and   a water flow field in fluid communication with the porous section of the at least one of the first separator plate and second separator plate.